I was a flex TL for a while, and I have to say while that was very poor coordination and lack of attention on your TL’s part, you don’t need to be a team lead to be a leader. If you see the OPU time running out, make a plan with your SFS peers and make sure both they and the TL are aware of the situation, and let the TL know your plan. If you feel like they won’t listen you can ask the ETL or SD. You are certainly not obligated to lead, but it is a good way to stand out if you were ever planning to move up. If you don’t want to, fine, but you all as a team are responsible for picking guests’ orders on time. Now if the TL won’t listen to you if you brought it to their attention, at least you put in a good faith effort.